- fixed an issue in old default file detection and in saving the factory defaults file

- in Preferences window removed the Import/Export Preferences buttons because they are redundant with the entries in the File -> Menu -> Backup. and added a button to Restore Defaults
- when in Basic mode the Tool type of the tool in the Geometry UI Tool Table after isolating a Gerber object is automatically selected as 'C1'
- let the multiprocessing Pool have as many processes as needed
- added a new Preferences setting allowing a custom mouse line width (to make it thicker or thinner)

flatcamGUI/PlotCanvas.py

@@ -310,6 +310,7 @@ class PlotCanvas(QtCore.QObject, VisPyCanvas):
             # Update cursor
             self.fcapp.app_cursor.set_data(np.asarray([(pos[0], pos[1])]),
                                            symbol='++', edge_color=self.fcapp.cursor_color_3D,
+                                           edge_width=self.fcapp.defaults["global_cursor_width"],
                                            size=self.fcapp.defaults["global_cursor_size"])
 
     def new_text_group(self, collection=None):